System for increasing realized secure sockets layer encryption and decryption connections

ABSTRACT

A system for increasing realized secure sockets layer (“SSL”) encryption and decryption connections is disclosed. The system combines monitoring of server load with adjustment of static SSL parameters to optimize a system of devices. The system monitors parameters of the servers that affect the ability of the servers to process SSL connections. An “SSL capacity” value for each server is calculated which represents the capability of that server to process SSL connections. This value is used to calculate an SSL threshold for that server, which is then applied to the SSL device to determine how many SSL connections the SSL device should process for that server. Since the connection threshold for an SSL device is a function of the device&#39;s load and each server&#39;s SSL capacity, and these values are dynamic, the connection threshold values are recalculated periodically to ensure increased SSL performance without impact to client response.

BACKGROUND

[0001] 1. Field of the Invention

[0002] Embodiments described herein are directed to a system for increasing realized secure sockets layer (“SSL”) encryption and decryption connections without significant impact to client response. The system combines monitoring of server load with dynamic adjustment of static SSL parameters to optimize an entire system of devices.

[0003] 2. Related Art

[0004] Secure Sockets Layer (“SSL”) is a protocol for transmitting private documents in a public data communication network. SSL operates by using a key to encrypt data that is transferred over an SSL connection. The SSL protocol typically uses Transmission Control Protocol/Internet Protocol (“TCP/IP”) and allows the following: 1) an SSL-enabled server to authenticate itself to an SSL-enabled client; 2) the client to authenticate itself to the server; and 3) both machines to establish an encrypted connection. An encrypted SSL connection requires the encryption by the sending software, and the decryption by the receiving software, of all information sent between a server and a client, thereby providing a high degree of confidentiality. Confidentiality is important for both parties to any private transaction. In addition, all data sent over an encrypted SSL connection is protected with a mechanism for detecting tampering—that is, for automatically determining whether the data has been altered from the point of transmission from the sending software until the data is received by the receiving software.

[0005] In current systems, SSL encryption and decryption devices (“SSL devices”) operate independently of the servers upon which they are performing the SSL operations. That is, they do not use information from the servers to determine loading of the device that is performing the SSL encryption and decryption. Load refers to the amount of data, i.e., traffic that the device carries. Parameters for configuring the SSL performance are static, if existent at all. When thresholds for the number of connections that an SSL device will accept are available, they are static because they are the only information available to the device. Without information about server loading, the SSL device cannot make dynamic choices or decisions. The SSL device can, for example, determine when it can no longer sustain more connections. The SSL device is unable, however, to determine which server can sustain the same. The result is that overall SSL performance of a system of servers and SSL devices, with the constraint of no significant client impact, is limited by the performance of the SSL device. This is because static algorithms that determine SSL offload to individual servers cannot meet a no significant-impact guarantee.

[0006] A system for increasing realized SSL encryption and decryption connections is thus designed to combine monitoring of server load with adjustment of SSL parameters to optimize the system of devices. The result of this dynamic system is increased SSL performance without significant impact to end-user response.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] A detailed description of embodiments of the invention will be made with reference to the accompanying drawings, wherein like numerals designate corresponding parts in the several figures.

[0008]FIG. 1 is a depiction of network connectivity of one SSL device and three servers.

[0009]FIG. 2 is a flowchart illustrating the optimization process of a system of one SSL device and three servers.

DETAILED DESCRIPTION

[0010] The following paragraphs describe a system for increasing realized secure sockets layer (“SSL”) encryption and decryption connections. An embodiment of the present invention includes an SSL encryption and decryption device (“SSL device”) that includes both hardware and software. The software contains the code that performs calculations and acts on the calculations.

[0011] According to one embodiment of the present invention, as illustrated in FIG. 1, a system 160 a includes one SSL device 120 located within a data communication network 110 between a set of three servers 140 a-c and a client machine 130. Coupled to one side of the data communication network 110 is the client machine 130. Meanwhile, a switch 135 acts as an intermediary between the SSL device 120 and the servers 140 a-c, whereby the switch 135 receives data from the SSL device 120 and then forwards the data to the servers 140 a-c.

[0012] This system 160 a is dynamically optimized within the data communication network 110.

[0013] The data communication network 110 may include the Internet, an Intranet, or any combination of public and private data communication networks. The data communication network 110 may be configured as a local-area network, wide-area network, or another kind of architecture. A multitude of systems, as depicted by 160 b-c, may further be sustained within the data communication network 110.

[0014] The client machine 130 attempts to open SSL connections to the servers 140 a-c. The SSL device 120 intercepts these connections, performs SSL encryption and decryption, and then sends the encrypted information to the appropriate server 140 a-c in an unencrypted format. For example, if client machine 130 attempts to open an SSL connection to server 140 a, the SSL device 120 intercepts the connection and opens it with client machine 130. The SSL device 120 then unencrypts the data sent over the connection and sends that data to server 140 a, unencrypted.

[0015] The system combines the monitoring of server 140 a-c load with dynamic adjustment of SSL device 120 parameters to optimize the entire system. The system, i.e. software running on some platform such as, but not limited to, an SSL device or a server, monitors certain parameters of the servers 140 a-c such as, but not limited to, CPU utilization and available memory, that are known to affect the ability of the servers to process SSL connections.

[0016] The servers 140 a-c may be monitored by many mechanisms. An agent, i.e., software, may be installed on the servers 140 a-c that then communicates to the SSL device 120. Windows NT has a protocol for remote monitoring of many types of server statistics, including CPU usage. UNIX operating systems support the remote execution of programs that can provide this information. In addition, Simple Network Management Protocol (“SNMP”) may also be used for monitoring.

[0017] As shown in FIG. 2, an “SSL capacity” value for each server 140 a-c is calculated and represents the capacity of that server 140 a-c to process SSL connections. This is illustrated in step 210 for server 140 a, step 220 for server 140 b, and step 230 for server 140 c. The calculation may be a direct value or a computation of values. Various algorithms may be used to determine such a value. One such algorithm is capacity=max [(# processors×processor speed in MHz/100)×(0.7−CPU utilization), 0]. Since SSL acceleration hardware may be present in some systems, another possible algorithm is capacity=max [(# processors×processor speed in MHz/100)×(0.7−CPU utilization)+f_(n)(x), 0], where f_(n)(x) represents the SSL acceleration capabilities of the SSL acceleration hardware.

[0018] The greater the SSL capacity of the server 140 a-c, the fewer SSL connections the SSL device 120 should process. The number of SSL connections processed by the SSL device 120 also depends on the load of the SSL device 120. Load is a direct value or computation such as, but not limited to, CPU utilization. Calculating the load of the SSL device 120 is shown in step 240. If an SSL device 120 is lightly loaded, it processes more SSL connections for all the servers 140 a-c than if it is heavily loaded.

[0019] As illustrated in step 250, the SSL capacity value is then used to calculate an “SSL connection threshold” for that server 140 a-c. This is applied to the SSL device 120 to determine how many SSL connections the SSL device 120 should process for that server 140 a-c, as shown in step 260. One algorithm for this calculation is threshold=10×server capacity×device CPU utilization. This represents the number of SSL connections that the SSL device 120 would allow to be processed by a given server 140 a-c.

[0020] Since the connection threshold for the SSL device 120 is a function of both the load of the SSL device 120 and the SSL capacity of each server 140 a-c, and these values are dynamic, the connection threshold values are recalculated periodically. The recalculation is based either on time or on additional thresholds that are functions of the SSL capacity and/or SSL device load. The result of this dynamic system is increased SSL performance without significant impact to client response.

[0021] While the above description refers to particular embodiments of the present invention, it will be understood to those of ordinary skill in the art that modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover any such modifications as would fall within the true scope and spirit of the present invention.

[0022] The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive; the scope of the invention being indicated by the appended claims, rather than the foregoing description. All changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. 

What is claimed is:
 1. A method of increasing realized secure sockets layer encryption and decryption connections comprising: monitoring at least one parameter of a server that is known to affect an ability of a device to process secure sockets layer connections; calculating a secure sockets layer capacity value for the server; calculating a load value for a secure sockets layer device; calculating a secure sockets layer connection threshold for the server; setting the secure sockets layer connection threshold for the server; applying the secure sockets layer connection threshold to the secure sockets layer device to be used in determining a number of connections for processing by the secure sockets layer device for the server; and recalculating the secure sockets layer connection threshold value for the secure sockets layer device.
 2. The method of claim 1, wherein the server parameter is CPU utilization.
 3. The method of claim 1, wherein the server parameter is available memory.
 4. The method of claim 1, wherein the secure sockets layer capacity value of the server represents a capability of the server to process secure sockets layer connections.
 5. The method of claim 1, wherein at least one of the secure sockets layer capacity value and the load value is a direct value.
 6. The method of claim 1, wherein at least one of the secure sockets layer capacity value and the load value is a computation of values.
 7. The method of claim 6, wherein the secure sockets layer capacity value=max [(# processors×processor speed/100)×(0.7−CPU utilization), 0].
 8. The method of claim 1, wherein the secure sockets layer connection threshold for the secure sockets layer device is a function of both device load and server capacity.
 9. The method of claim 8, wherein device load and server capacity are variable values.
 10. The method of claim 8, wherein the connection threshold=10×server capacity×device CPU utilization, represents the number of secure sockets layer connections that the secure sockets layer device allows a server to process.
 11. A computer readable medium having computer readable instructions encoded therein to: calculate a secure sockets layer capacity of a server; calculate a load of a secure sockets layer device; calculate a secure sockets layer connection threshold for the server; set the secure sockets layer connection threshold for the server; apply the secure sockets layer connection threshold to the secure sockets layer device; and recalculate the secure sockets layer connection threshold value for the secure sockets layer device.
 12. The computer readable medium of claim 11, wherein the secure sockets layer capacity of the server represents a capability of the server to process secure sockets layer connections.
 13. The computer readable medium of claim 11, wherein the secure sockets layer capacity is a direct value or a computation of values.
 14. The computer readable medium of claim 13, wherein the secure sockets layer capacity=max [(# processors×processor speed/100)×(0.7−CPU utilization), 0].
 15. The computer readable medium of claim 11, wherein the load is a direct value or a computation of values.
 16. The computer readable medium of claim 11, wherein the secure sockets layer connection threshold for the secure sockets layer device is a function of both device load and the secure sockets layer capacity of the server.
 17. The computer readable medium of claim 16, wherein the device load and the secure sockets layer capacity are variables.
 18. The computer readable medium of claim 16, wherein the secure sockets layer connection threshold determines a number of connections that the secure sockets layer device processes for the server.
 19. The computer readable medium of claim 16, wherein the secure sockets layer connection threshold=0×server capacity×device CPU utilization.
 20. A system for providing a secure sockets layer connection within a data communication network comprising: a secure sockets layer encryption and decryption device; a client machine; and at least one server wherein the system is adapted to: monitor at least one parameter of a server that is known to affect an ability of the server to process secure sockets layer connections; calculate a secure sockets layer capacity value for the server; calculate a load value for the secure sockets layer encryption and decryption device; calculate a secure sockets layer connection threshold for the server; set the secure sockets layer connection threshold for the server; apply the secure sockets layer connection threshold to the secure sockets layer encryption and decryption device to determine a number of connections for processing by the secure sockets layer encryption and decryption device for the server; and recalculate the secure sockets layer connection threshold value for the secure sockets layer encryption and decryption device.
 21. The system of claim 20, wherein the data communication network includes at least one of an Internet or an Intranet.
 22. The system of claim 20, wherein a secure sockets layer encryption and decryption device within the data communication network includes software for performing calculations.
 23. The system of claim 20, wherein the server parameter is at least one of CPU utilization and available memory.
 24. The system of claim 20, wherein the secure sockets layer capacity value=max [(# processors×processor speed/100)×(0.7−CPU utilization), 0].
 25. The system of claim 24, wherein the secure sockets layer capacity value of the server represents a capability of the server to process secure sockets layer connections.
 26. The system of claim 20, wherein the secure sockets layer connection threshold=10×server capacity×device CPU utilization.
 27. The system of claim 26, wherein the secure sockets layer connection threshold for the secure sockets layer device is a function of device load and server capacity, both of which are variable values.
 28. The system of claim 20, wherein at least one of the secure sockets layer capacity value and the load value is a direct value.
 29. The system of claim 20, wherein at least one of the secure sockets layer capacity value and the load value is a computation of values. 